YouTube buffering — fix it

YouTube HD needs 5 Mbps sustained, 4K needs 25 Mbps. Plus reliable CDN reach.

YouTube buffering means sustained throughput dropped below the bitrate of the video stream you're watching. YouTube uses adaptive bitrate aggressively — buffering = sustained throughput drop.

Signalyzr measures sustained throughput (not peak) and CDN reachability — the actual metrics that decide whether YouTube buffers.

What this measures

  • Sustained download (needs to be ≥ 5 Mbps for HD, 25 Mbps for 4K)
  • Latency to nearest probe
  • DNS resolution time

How it works

  1. Test
  2. Compare against the threshold
  3. Identify cause
  4. Fix

Why this matters

Peak speed lies. YouTube needs SUSTAINED speed. Signalyzr measures sustained.

Top fixes

  • If speed is fine but YouTube buffers: try changing DNS to 1.1.1.1
  • If only YouTube buffers (other sites fine): try YouTube on a different device — possibly app cache
  • If everything buffers: it's connection-wide (speed, jitter, packet loss)

FAQs

Why does YouTube buffer in HD when speed test says 200 Mbps?

Speed tests measure peak. Streaming needs sustained over 5-10 minutes. ISP throttling, CDN issues, or Wi-Fi dropouts can be invisible to a 15-second speed test.

Is YouTube blocked by my ISP?

Rare in India. Almost always either weak Wi-Fi, peak congestion, or app cache issues. Diagnose first.

Diagnose YouTube →

Related

Signalyzr is a free, privacy-first network diagnostic tool made in India. Loading the diagnostic app…